Vehicles are typically equipped with suspension systems that include a multitude of springs, linear actuators, damper assemblies such as shock absorbers and/or struts, interconnecting support members, and the like that contract and expand to provide flexible relative movement between the body and chassis. During normal driving conditions, these components gradually dissipate the forces generated by bumps, potholes, and other road surface anomalies in a controlled manner that helps the driver to maintain control over the vehicle and provides passengers a comfortable driving environment.
However, severe impact events can impose excessive loading on a suspension causing it to contract beyond the designed operating range of springs and shocks/struts. Excessive jounce, or downward motion of the body toward the chassis, can lead to potentially damaging collisions between suspension components and/or other undercarriage elements. To prevent such damage, many suspension systems employ impact load management systems that limit jounce. Such systems typically include jounce bumper assemblies configured to engage during severe impact events and provide a “bottoming” or a limit to further contractive motion. These assemblies may be used to limit jounce between, for example, sprung and unsprung vehicle masses and may be conveniently located within the body of a shock or strut. Such integrated assemblies typically include a rigid metallic striker plate coupled to the end cap of the damper tube and a polyurethane foam-based or rubber jounce bumper coupled to the upper mount. Each is aligned along a common piston rod and spaced apart so that, during an impact event, the striker cap and jounce bumper engage causing the bumper to deform axially along the piston rod in the direction of loading. However, such a configuration provides little cushioning effect from impact loads because of the rigidity of the striker plate and the marginal capacity of the foam bumper to absorb associated energy. As a result, striker plates, jounce bumper mounts, and/or other rigid impacting surfaces can receive the brunt of impact loads making them susceptible to damage. Accordingly, these and other similarly affected elements including the chassis frame and vehicle body structure are generally designed with a more rugged construction of greater mass and volume than would otherwise be required if the jounce bumper assembly were more energy absorbing. Such a design adds to the overall weight and expense of damper assemblies, and reduces their space efficiency.
Accordingly, it is desirable to provide a jounce bumper assembly for managing impact load in a vehicular suspension system that enables the use of lighter weight supporting materials without adversely impacting other desirable vehicle characteristics such as driving comfort or vehicle controllability. Further, it is also desirable if such a system has improved space efficiency whether loaded or unloaded and improved geometric stability under loading. Furthermore, it is also desirable if such a geometrically stable design provides improved energy absorption and reduced peak strain. Furthermore, other desirable features and characteristics of the present invention will become apparent from the subsequent detailed description and the appended claims, taken in conjunction with the accompanying drawings and the foregoing technical field and background.